Draft-gear.



.J-. 'J. HOFFMAN.

DRAFT GEAR.

APPLICATION FILED JULY 9, 1906.

1,047,225, Patelited Dec,1'7,1912.

3 SHEETS-SHEET 1.

v Inveniam i m y Y QQMJQQMAL J. J. HOFFMAN.

DRAFT GEAR.

APPLICATION FILED JULY 9, 1906.

1,047,225, Patented Deb. 17,1912.

3 SHEETS-SHEET 2.

J. J. HOFFMAN.

. DRAFT GEAR. APPLICATION FILED JULY 9, 1906.

1,047,225, Patented Dec.,17, 1912.

a SHEETS-SHEET s.

Wrzessesd UNITED snares. PATEN orrroij.

JOHN J. HOFFMAN, or'sT. LOUIS, MissoURI, ASSIGNOB TO PETER H. MURPHY, or str LOUIS, MISSOURI.

DRAFT-GEAR.

and quick initial movement thereof and a' gradually decreasing speed and an increasing leverage resistance; and to attain further advantages hereinafter more fully set forth.

The invention consists in the parts and in the arrangements and combinations of parts hereinafter described and claimed.

In the accompanying drawings, which form part of this specification, and wherein like symbols refer to like parts wherever they occur, Figure 1 is a plan view showing a portion of the draft timbers of a railway car with the draft gear in position; Fig.- 2 is a longitudinal section on the line 22 of Fig. 1, showing parts of the draftv gear in side elevation; Fig. 3 is an enlarged View showing the box-casting and follower-plates in horizontal section, and showing the cam levers, movable abutment-casting and springs in plan; Fig. 4: is a horizontal section showing the working parts in action; Fig. 5 is an end view of the box-casting showing the cam levers in normal position; Fig. 6 is a longitudinal vertical section through the box-casting with the working parts removed to show the seat portions for the levers and. the stop lugs for the movable abutmentcasting; Fig. 7 is a fragmentary vertical section similar to Fig. (l, but showing the stop lugs on the opposite side of 'the cast ing: Fig. 8 is a perspective viewof the abutment-casting; Fig.0 is a perspective view of one of the pair of cam levers; Fig. 10

is a similar view of said cam lever invert- .ed; and, Fig. 11 is a perspective view of the single CilllllGVQI'.

The draft ear is ada ted to be mounted a bet-ween flan ed cheeklates or other snitable guide-ways. 1 provided therefor on the Specification of Letters Patent.

, Application filed. July. 9, 1906; Serial No. 325,196.

Patented Dec. 17-, 1912.

a housing for the working parts of the mechanism is formed with rounded pocketson each side near the end. These pockets are adapted to receive cylindrical hinge-portions 5 of cam levers 6. 'A circular bore '7 Go is provided in each of said cylindrical hinge portions 5 and through said bores 7 extend pivot pins 8. The ends of the pivot pins 8 project beyond the hinge portions into 7 outwardly flaring perforations in the too and. bottomiof the box-casting 3 in which they are riveted. The outer faces 9 of the levers 6 are curved to constitute cams. portion of the inner" face of -each of said levers adjacent to its pivot is straight or flattened as at 10,,a-nd theendmost portion of said inner face is'curved towardthe outer face to constitute a cam portion ll. Both the outer and the inner surfaces of the cam levers are convex, and the cam levers'are 7 5 counterparts of each other. They are pivotally mounted'on opposite sides of the box casting and are arranged transversely to the line of'draft so as to be movable in suhstam,

tially the same plane- By reason of this symmetrical arrangement, the forces acting on the structure are restricted to a region close to the axis thereof. I K A movable abutment-casting 12 'is arranged to reciprocate withinthe box-casting 3.. This abutment-casting is formed w th a plain outer or forward. face 13 against which the inner faces of the cam levers 6 hear. The opposite or inner face 14: of the i v abutment-casting is provided with a central boss 15 which is adapted to center a coiled spring 16- interposedbet-ween said face 1% and a follower-plate 17fouiside of, the box:

casting. Surrounding said qnring-lfi is a heavier spring 19,. which also bears'against'95 and-the followerthe abutment-casting 1.9 plate 17. For the purpose of limiting the longitudinal movement of the abutment-casting 12, stop lugs 19 are provided on the inner faces of the side walls of the bococasting 3.

Preferably, the abutment-casting has its forward or outermost end reduced top the stop lugs" which are arranged to int'ei oept the enlarged rar or innermost end 1 20 of said abut1nent-casting2 he second fob lower-plate2l is arranged beyond the front end of the box-casting in position for the outer cam faces 9 of the cam lovers 6 tobear against. The two follower-plates 1'7 and 21 The .move the now are arranged to slide endwise in the cheekplates 1 or other suitable guides mounted on the draft sills, and their outermost posltions are limited by stops 26 provided thereon. The follower-plates 17 and 21 are normally held by. the springs 16, 18 in their outermost positions against their respective back stops at a short distance from the" end of the boxcasting 3. A U-shapedstrap or yoke 2% is looped around the follower plates 17 and 21 and is connected at its forward ends to the'dra-yvbar 25 of a coupling in the usual manneil';

In the normal position of the parts, the abutment-casting is held against its back stops l9, and bears against the inner faces of the cam levers 6 at points closer to the fulcrums than at any other position of the parts, In this normal position, the outer faces 9 of the cam levers 6 bear against the follower-plate 21 at points farther from the fulcrum than at any other position of the camlevers In the operation of the device, the points of bearing ofthe cam levers change continuously, the distance of the bearing point of the inner face from the fulcrum increasing continuously, while the distance of the bearing point of the outer face decreases continuously. In consequence of this arrangement, the force required to move said levers inwardly increases continuously. In order to increase the area of contact be tween the cam levers and the follower-plate 21, when the levers 6 are in compressing action, and also to strengthen said levers at the point of juncture with their hinge portions 5, wings 22 are formed integral with said levers and the outer faces of said wingsare curved in conformity with the cam faces 9. The levers (3 are preferably cored out, as indicated at 23 in the. drawing to redu ce tlieirweight.

In the operation of theherein described draft gear, the initial pull on the drawbar and yoke connected thereto, will move the follower-plate 17 toward the box-casting 3. This movement of the follower-plate initially compresses the springs 16 and 18 until the follower-plate abuts against the end of the box-casting 3. During this initial movement the movable abutment-casting 12 "is in engagement with stop lugs 19. A continued heavy pull will connected follower-plate and box-casting toward the follower-plate 21 which plate serves in this instance as an abutment. When the parts are thus moved toward the plate 21 the cam levers 6 are brought into action and caused to swing inwardly against the movable abutmentcastmg 12. The abutment-casting is thus moved inwardly and thereby further compresses said springs 16 and 18. Owing to the peculiar shape of the cam lethe parts will be moved much. more easily and rapidly at the beginning of the action and with gradually increasing difficulty and slowness toward the end oftheir movement. The action of the cam faces in moving zIClOSSllIG faces of the follower-plate and abutment-casting also offers a greater amount of leverage resistance. The builing as the draft action, except that the followerplate 21 and box casting 3 are initially moved toward the follower-plate 17 which serves asan abutment in such instances.

'By the arrangement of parts herein described a simple and effective mechanism is produced which will absorb the shock due to a sudden or heavy pull upon the draft appliances, and it is also effective during bufling action.

It is preferable to arrange the cam levers 6 as shown in the drawings. That is, to mount a pair of levers on one side of the box-casting and a single lever on the opposite side, adapted to work between said pair of levers. But it is obvious that the arrangement of a plurality of cum levers may be modified within the spirit of the invention.

Obviously, my device is capable of considerable modification within the scope of my invention, and therefore I do not wish to be limited to the specific construction shown and described. i What I claim is: i

1. A draft gear comprising guides, a follower mounted to move in said guides, a second follower opposed to said follower, a box-casting interposed between said followers'and normally spaced therefrom but movable against them respectively, a movable abutment mounted within saidbox castmg, a spring interposed between said first ment oned follower and said movable abutment within said box-casting, and cam levers pivotally mounted in said box-casting and interposed between said movable abutment and said second follower.

2; A friction draft gear including guides. a followermovable in said guides, a box casting movable in said guides, limit stops for said follower and box-casting, a yield- Ingabutment in said box-casting, and cam levers pivotally mounted in said box-casting and interposed between said follower and said yielding abutment, said cam levers hav- In conse action of the gear is substantially the same ing increased surface area near their fulcrum, and being shaped and arranged so that motive force is initially applied at a point distant from the fulcrum and progressively moved toward'said fulcrum, and the point of action upon said yieldingabut= ment is progressively. moved from-said fulcrum, whereby said working parts can be moved easily' and quickly at the beginning and gradually slower with increasing leverage resistance.

3. A draft gear comprising guides, a boxcasting movably mounted in said guides, followers opposed to said box-casting and normally spaced therefrom but movable against it, a movable abutment mounted within said box-casting and yieldin'gly heldin normal position, and transversely arranged cam levers pivotally mounted in said box-casting in alinement with and interposed between said movable abutment and one of said followers.

4. A draft gear comprising guides, a boxcasting movably mounted in said guides,

' followers opposed to said box-casting and normally spaced therefrom, a movable abutment mounted within said box-casting and yieldingly'held in normal position, and cam levers pivotally mounted-in said box-casting 30. in alinement with and interposed between said movable abutment and one of said followers, said cam levers being so shaped and arranged that the point of contactwith said follower is initially at'the greatest distance from the fulcrum, and the initial point of its contact with the movable abutment is at its shortestdistance from the fulcrum, whereby said. working parts can be moved easily and quickly at the beginning and gradually 40 slower and with increasing leverage resistance until said followers bear-against said box-casting.

5. A draft gear comprising guides, followers movable in said 'guides,-a box-casting movable in said guides and normally spaced from said followers, limit stops for said f0llower and box-casting, a yielding abutment in said box-casting, and cam levers pivotally mounted in said boX-casting in alinement with and interposed between one of said followers and said yielding abutment.

' 6. A draft gear comprising guides, followers movable in said guides, a box-casting movable in said guides and normally spaced from said followers but arranged to abut against them in operation, limit stops for said follower and box-casting, a yielding abutment in said box-casting, and cam levers pivotally mounted in said box-casting in alinement with and interposed between one6 0 of said followers and said yielding abutment, said cam levers being so shaped and arranged that the point of contact with said; first-mentioned abutment is initially at the greatest distance from the fulcrum, and the initial point of its contact with the movable abutment is at its shortest distance from the fulcrum, whereby said working parts can be moved easily and quickly at the beginning I and gradually slower and with increasing '70 leverage resistance.

In testimony whereof I have signed my name to this specification in' the presence of two subscribing witnesses this 6th dayof July, 1906.

JOHN J. HGFFMAN.

Witnesses:

JAMES A. CARR, G. A. PENNINGTON.

Copies of this patent may be obtained for five centseaeh, by addressing the Commissioner of Patents, Washington, D. 0. 

